In recent years, large amounts of information of various kinds are provided through the wide use of the Internet, and it has become difficult to promptly retrieve information requested by a user. The large amounts of information contain information that has a meaning in being distributed at the current location of each user. Therefore, there is a demand for distribution of location-dependent information to users.
Concerning such a type of technique, The GPS (Global Positioning System) has been installed in portable telephone devices based on mandatory function that a portable telephone device notifies of the caller location information in emergency calls, thereby there is a service to provide location-related information to a terminal having a positioning function.
Also, there have been systems designed for providing location-related information concerning the locations of users to terminals (user terminals) not having a positioning function such as the GPS, using location information supplied from terminals (positioning terminals) having a positioning function, as disclosed in Patent Documents 1 and 2.
In each system disclosed in Patent Documents mentioned below, a mapping table that associates user terminals with positioning terminals is stored beforehand in an information providing server, and location-related information generated in accordance with location information supplied from positioning terminals is distributed to the corresponding user terminals.